Functional characteristics of glaucoma related arcuate defects seen on OCT en face visualisation of the retinal nerve fibre layer

Ophthalmic Physiol Opt. 2021 Mar;41(2):437-446. doi: 10.1111/opo.12780. Epub 2021 Jan 25.

Abstract

Purpose: To assess continuity of perimetric defects corresponding to arcuate defects seen on optical coherence tomography (OCT) en face reflectance images of the retinal nerve fibre layer (RNFL) in patients with glaucoma.

Methods: Seven patients with glaucoma who had arcuate structural defects on OCT RNFL en face images were recruited. Static suprathreshold stimuli were presented along different meridians to localise perimetric defects in the corresponding hemifield. Then two contrasts, one 6 dB greater than the other, were used with kinetic perimetry to assess the slope of the defect. Findings with kinetic and 24-2 perimetry were compared.

Results: Static perimetry found that regions of perimetric abnormality spatially corresponded with the regions of en face RNFL hyporeflectivity. Kinetic perimetry found that the slopes of the edges of the defects ranged from 3-12 dB degree-1 , and that the functional abnormalities were continuous with the physiologic blind spot even when the 24-2 protocol only showed paracentral defects.

Conclusions: Perimetric abnormalities and arcuate RNFL en face defects were spatially correspondent. Perimetric testing guided by OCT en face reflectance images can reveal greater functional detail of glaucomatous abnormality than 24-2 testing.

Keywords: OCT; arcuate defect; en face images; glaucoma; perimetry; retinal nerve fibre layer.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Aged
  • Female
  • Glaucoma / diagnosis
  • Glaucoma / physiopathology*
  • Humans
  • Intraocular Pressure / physiology*
  • Male
  • Middle Aged
  • Nerve Fibers / pathology
  • Optic Disk / diagnostic imaging*
  • Reproducibility of Results
  • Retinal Ganglion Cells / pathology*
  • Tomography, Optical Coherence / methods*
  • Visual Acuity*
  • Visual Field Tests / methods
  • Visual Fields / physiology*